Bimodal gate-dielectric deposition for improved performance of AlGaN/GaN metal–oxide–semiconductor high-electron-mobility transistors

Abstract

A bimodal deposition scheme combining radiofrequency magnetron sputtering and plasma enhanced chemical vapour deposition (PECVD) is proposed as a means for improving the performance of GaN-based metal–oxide–semiconductor high-electron-mobility transistors (MOSHEMTs). High-density sputtered-SiO2 is utilized to reduce the gate leakage current and enhance the breakdown voltage while low-density PECVD-SiO2 is employed to buffer the sputtering damage and further increase the drain current by engineering the stress-induced-polarization. Thus-fabricated MOSHEMT exhibited a low leakage current of 4.21 × 10−9 A mm−1 and high breakdown voltage of 634 V for a gate–drain distance of 6 µm, demonstrating the promise of bimodal-SiO2 deposition scheme for the development of GaN-based MOSHEMTs for high-power application.

Thermal and Thermoelectric Properties of Graphene

“…The corresponding research could help us to find approaches to effectively control thermal conduction. As applications, thermal conduction of materials can be improved for solving the serious heat dissipation and breakdown in ever‐smaller electronic devices, or suppressed for realizing thermal insulation in high‐power engines and also for enhanced thermoelectric efficiency …”

Ga Adlayer Coverage and Surface Morphology Evolution during GaN Growth by Plasma-assisted Molecular Beam Epitaxy

“…In this study, the Ga surface coverage during plasma-assisted molecular beam epitaxy (PAMBE) of GaNis carefully reviewed. We systematically investigate the surface morphology under various Ga/N flux ratios, and verify that a Ga adlayer with a total coverage of about 2.5 monolayers (ML) is the most energetically favorable surface structure forGaN, resulting in a high adatom diffusion rate and a planarized morphology [2]. The kinetic process of Ga adsorption and desorption is studied and the critical Ga incident flux under a certain N flux is obtained in order to produce the optimized Ga/N flux ratio.…”

“…Due to many favorable electronic properties such as high critical breakdown field and high saturation electron velocity, GaN has become a very promising candidate material for high-frequency, high-power, and high-temperature electronics [1][2][3][4][5][6][7]. However, due to the lack of suitable substrate for GaN epitaxial growth, GaN crystal quality becomes the bottleneck to limit the device performance [8].…”

YN nanostructure formation on the GaN(0001) surface: First principles studies

“…GaN is currently found in a large variety of applications such as high power, high temperature and high electronic mobility devices [1][2][3][4][5][6]. Also, a strong inter-sub-band absorption peak located at 675 meV in AlGaN/GaN super-lattices has been found, so that it is possible to apply these heterostructures in devices which work in the mid and near-infrared [7,8].…”